Internal combustion engine



Dec. 6, 1932. o. H. ERICKSON INTERNAL COMBUSTION ENGINE Filed June 22, 1929 2 Sheets-Sheet l Iii'im abbina Ew -.HI

Dec- 5, 1932' o. H. ERICKSON INTERNAL COMBUSTION ENGINE Filed June 22, 1929 2 Sheets-Sheet 2 alitozneq Patented Dec. 6, 1932 UNITED STATES ATF? INTERNAL COMBUS'IION ENGINE Application filed .Tune 22,

rlhis invention relates to internal combustion engines and especially to those known as two-cycle or two-stroke engines and more especially to those provided with independent working and auxiliary cylinders.

he main object of my invention is to improve the explosive action of the gasoline vapor, whereby a large increase in power and a decrease in gasoline consumption is attained. ln the furtherance of this main object the invention consists in certain new relations between the movements of the several parts, whereby the volatilization of the fresh vapor is greatel7 increased while still at a low pressure, and whereby when said fuel is compressed and ignited, it pronuces a substantially instantaneous and complete combustion resulting in an explosion of great power. Another object of my invention is to provide a mea-ns whereby the cylinder casting or block may be of uniform height and yet the upper end of the auxiliary cylinder is adjacent to, or lower than, the middle point of the working cylinder, thereby permitting the transfer passage to be only as long as the thickness of the cylinder wall. Another object is to provide a means whereby the clearance in the working cylinder may be kept low in spite of the fact that the piston therein is provided with an upward extending lip or deflector. Another object is to provide a means of admitting fuel into the working cylinder at a point positioned above the exhaust ports thereof. Another object is to provide an auxiliary inlet port in the working piston itself, whereby the transfer of fuel into the working cylinder may continue until the auxiliary piston has reached the end of its stroke. Another object to provide a means whereby the spark is brought close to the working piston. Other objects are to produce an engine of eXtreme simplicity of construction and in which the improved cycle will produce improved results in power and in economy.

l attain these and other objects by the devices. mechanisms and arrangements illustrated in the accompanying drawings, in which Fig. lis a vertical section of an engine made in accordance with m r invention and pro- 1329. Serial No. 372,332.

vided with two sets of working and auxiliary cylinders, showing the working pistons at the beginning and end of their respective strokes; Fig. 2 is a similar view thereof, showing the parts in the positions when the crank-shaft has turned through a right-angle; Figs. 3, el, 5, and (i are diagrammatic views showing the cranks, connecting rods, and pistons in the positions of the several working parts of Figs. 'i and 2, in their consecutive order; Figs. 7, 8, and 9 are sections of that part of the engine containing the transfer port between the auX- iliary cylinder and the working cylinder, showing the several moving parts in their po- Sitions when the working crank has turned into several consecutive positions, as follows-in Fig. 7 the crank being about 45 degrees further than shown in Fig. 5, or earlier than in Fig. et, in Fig. 8 it is 30 degrees further than in Fig. a, and in Fig. 9 it is 60 degrees further than in Fig. l, or 3() degrees earlier than in Fig. 6; Fig. l0 is a vertical cross-section of the engine taken on the line lO--lO in Fig. l2; Fig. il is a similar view taken on the line ll-ll in Fig. 12; Fig. 12 is a plan view of a part of said engine, showing the cap of the right-hand auxiliary cylinder removed; and Fig. 13 is a view ysimilar to Figs. 7 to 9, on a larger scale, showing the moving parts in their positions when the working crank is in the position shown in Fig. 6 and on the right-hand end of Fig. 2.

Similar numerals of reference refer to similar parts throughout the several views.

The engine illustrated in the drawings is provided with two working cylinders l and two auxiliary cylinders 2, each working cylinder having one auxiliary cylinder, all cast in a single block which is provided with three suitable crank-shaft bearings 3. A waterjacket l is cast into the block and surrounds the cylinder walls except where the working and auxiliary cylinders contact, there being a single thickness of metal forming the wall between the said cylinders.

The two working cylinders 1 are similar to each other and each comprises a straight bore provided with two oppositely positioned sets of three exhaust ports 6, which pass throughthe block and lead to suitable eX- haust manifolds 7 on the two sides of the engine. The said exhaust ports 6 are so positioned in the cylinders 1 that they are fully uncovered by the working piston 8, when it is at the lower end of its stroke. The working cylinder 1 is also provided with a transfer port 9, positioned radially of the cylinder at right-angles to the position of the said exhaust ports 6, and passing through the separating wall 5 of theblock said port 9 being positioned axially above the exhaust ports 6 a4 distance substantially corresponding with the distance from the top of the working piston 8 to the lower outer edge of the deiector lip 10 of the said piston 8, as hereinafter described, so that the exhaust ports 6 will be opened substantially at the same time that the lip 10 uncovers the transfer port 9, as shown in Fig. 7.

The upper end of each working cylinder 1 is closed by a cap 11, secured to the block, and having a deep cylindrical depression, cavity or pocket 12 therein, extendingdown into the cylinder 1 and being eccentrically placed therein to permit the lip 10 to passbeside it, and of less diameter than the cylinder bore, thereby reducing the clearance space of the cylinder 1, and adapted to contain and support the spark-plug 13 for the cylinder, thus bringing the igniting spark close to the working piston 8.

The two auxiliary cylinders 2 are similar to each other and of the same dimensions as the main'or working cylinders 1, and each comprises a straight bore provided with two ports. One of these ports is the transfer port 9 leading therefrom through the wall 5 into the working cylinder 1, as above described. The other said port is the intake port 14 and is positioned radially at right-angles to the said transfer port 9, and is connected by a suitable manifold 15 to the carburetor or other source of supply of mixed air and fuel vapor. The axial position of this port 14 below the transfer port 9 is substantiallyequal 4to the stroke of the eccentric operating` tho sleeve, hereinafter described.

'The upper end of the auxiliary cylinder 2 is also provided with an entirely independent cap 16, which is secured to the upper end of the block, and which is provided with a deep cylindrical depression, cavity or pocket 17 extending down into the cylinder 2. The upper end of this pocket 17 fits neatly in the cylinder 2, and the lower part thereof is offset inward therefrom so that the lower end is of less diameter than said cylinder 2, thereby providing` an annular space 18 between it and the cylinder walls. This annular space 18 is adapted to receive the upper end of the sleeve, hereinafter described.

The cavity 17 in the auxiliary cylinder 2 extends downward a greater distance therein than the corresponding cavityV 12 in the working cylinder l. The lower' end of the cavity the crank 17 extends to within a short distance of the position of the top of the auxiliary piston 19, reciprocating in the hereinafter described sleeve, when it is at the upper end of its stroke. also provided with an outlet passage or groove 20 which is positioned vopposite to and leads to the upper edge of the above-described transfer port 9 in the dividing wall 5 between the two cylinders 1 and 2.

The sleeve 21 fits in the auxiliary cylinder 2 and in the space 18 and is adapted to recip rocate vertically therein. The sleeve 21 is provided with two ports 22 and 23 which are axially alined with each other. The intake port 22 of the sleeve 21 is radially alined with the intake port 14 of the cylinder 2in which it moves, and the transfer port 23 of the sleeve 21 is radially alined with the transfer port 9 of the cylinder 2. The sleeve 21 is given a very short movement of about ones quarter that of the working and auxiliary pistons, by means of an eccentric mounted on the main shaft of the engine, hereinafter described.y The said ports 22 and 23 are positioned axially in the sleeve to permit the full opening of the respective intake and transfer ports at the ends of its stroke.

The crank-shaft 24 of the engine is mounted in the three bearings 3 and is symmetrical about theV central bearing, except that the cranks and eccentrics thereof on the one side of the bearing are set at 180 degrees from those on the other side of the bearing. The main or working cranks 25 are positioned next to the outer bearings. The auxiliary cranks 26 `are positioned next to the cranks 25 and terminate in a circular plate or disk 27. The eccentrics 28 are formed on the side of the plates 27 and are positioned on each side of the central bearing. yThe crank 26 is positioned ninety degrees ahead of the workingcrank 25, and the eccentric 28 is centered about seventy-six degrees in advance of the said auxiliary crank 26.

The main or working piston 8'is connected to the crank 25 by means of a connecting rod 29. The auxiliary piston 19 is connected to 26 by the connecting rod 30. The sleeve 21 is connected to the eccentric 28- by means of the strap and connecting rod 31.

4The main or working piston 8 is of normal construction in its lower portion but is provided with an upward extending deflector 32 at its upper inner end, and with a. passage'33 through its lower end and in line with the top of the piston 8. This lip 10'is positioned and is adapted to close the above-mentioned transfer port 9 through the wall 5.

The auxiliary piston 19 reciprocates in the sleeve 21 -and may be of normal construction. Since the cylinder 2 is of the same dimen` sions as the cylinder 1, and the sleeve 2l lits in the cylinder 2, and the piston 19 fits in the sleeve 21, it followsthat the piston 19 is vof The lower end of this pocket 17 isv somewhat less diameter than the piston 8. lt is also of less length, but its axial motion in the sleeve is equal to that of the working piston S.

The connecting rod 30 of the auxiliary piston 19 is shorter than the connecting rod 29 of the working piston 8, thus bringing the upper end of the travel of the auxiliary piston slightly below the central point of the travel of the working piston 8.

Description of the action of the engine TWhen the crank-shaft 24tis in the position indicated in Fig. 6, the auxiliary piston 19 is at the upper end of its stroke, as shown on the right-liand .side of Fig. 2 and as in Fig. 13. In this position the piston 19 does not quite cover the sleeve ports 22 and n3 and is substantially stationary, while the sleeve 21 is moving downward at its highest speed. Also, at this time, the upper `end of the sleeve transfer port 23 is only .slightly above the lower edge of the cylinder transfer port 9 and, a momentlater, this port 9 is closed by the downward moving sleeve 21. As the crank-shaft 2e rotates, the auxiliary piston 19 passes downward, with the sleeve 21, and causes a slight vacuum in the space above it until the sleeve intake port 22 uncovers trie intake port 1st in the cylinder 2 and the auxiliary piston 19 further uncovers the sleeve intake port 22. By the time the crank-shaft 24 has reached the position shown in Fig. 3, and the left-hand part of Fig. 1, the sleeve 21 has substantially stopped its downward motion and the sleeve port 22 is in line with the intake port 14: of the cylinder, fully opening it, and the auxiliary piston 19 draws in fresh fuel freely.

lllhen the crank-shaft 24 turns into the position shown in Fig. 5, and the left-hand part of Fig. 2, the` sleeve 21 has risen to close the intake port 14 and the auxiliary piston 19 is now at the lower end of its stroke and the sleeve is full of fresh fuel vapor at sub stantially atmospheric pressure, and, on further turning of the crank-shaft, the auxiliar-y piston 19 rises and compresses this fuel slightly and then, when the parts are about one-half way between the positions shown in Figs. 5 and Ll, the parts occupy the positions shown in Fig. 7. At this time the upward moving sleeve has already partially opened the port 9 with the port 23, and the other side of the port 9 is just being opened by the downward moving lip 10 on the working piston 8, and therefore, the hot, high pressure gases in the working cylinder 1 momentarily pass into this auxiliary cylinder 2, through said port 9, as shown in Fig. 7, until the pressure therein is equal to the decreasing pressure in the working cylinder 1, which is simultaneously exhausting its gases through its exhaust ports 6, as hereinafter describe-d. This action is extremely fast becomes very finely volatilized. The advancmg auxiliary piston 19 increases this pressure in the auxiliary cylinder 2 lso that this highly i..

volatilized fuel is transferred through the now open sleeve port 23 and transfer port 9 into the working cylinder above the lip 10 and is projected upward therein by means of the deile'ctor 32 on the working piston 8, as shown infFig. 3. On further turning of the crank-shaft 24, the transfer port 9 is momentarily closed by the lip 10 on the piston 8, as shown in Fig. 9, and is then opened by the passage 33 through the lip 10 so that, when the auxiliary piston 19 has reached the upper end of its stroke (Figs. 6 and 13) all of the fuel has been transferred into the working cylinder 1.

At this time the working cylinder full of slightly compressed hot vapor and its piston 8 is moving upward and, at once, closes the transfer port 9. The upward-moving working piston 8 then compresses this vapor in the werking cyl nder 1, as the crank-shaft 211 turns from the position shown in Figs. 6 and 13 to that shown in Fig. 3, until it reaches the upper end of its stroke (Fig. 3), when said gases are fully compressed and ready for` ignition. lWhen the spark ignitei this gas ft is not only at a high pressure but it is hot and is so thoroughly mixed and volatilized that the flame from the spark travels with substantially instantaneous action throughout the entire body of vapor, resulting in complete combustion thereof and causing the pressure of the gas to rise on steep gradient and eliminating the losses usually experienced through the delay in ignition, or the sluggish burning, of the vapor, and through the incomplete combustion, due to improper volatilization of the vapor in the usual working cylinder.

As the crank-shaft 24 turns further from the position shown in Fig. 3 to that shown in Fig. 5, the pressure formed by this explosion does its work on the descending piston and the gases are somewhat cooled by expansion. At this point (Fig. 5) the said transfer port 9 is open on the working cylinder end bf its connection with the passage 33, but is closed on the auxiliary cylinder end by the sleeve 21, and therefore the expanding gases cannot escape through said port 9 until the crankshaft 24 has reached a position substantially half-way between those shown in Figs. 5 and l with the parts in the posi tions shown in Fig. 7. At this point the lip 10 uncovers the transfer port 9 and the upward rising sleeve 21 has already partly uncovered the auxiliary end of said port 9 and ythe upper edge of the working piston 3 uncovers the exhaust ports 6. The workedout, expanded, gas passes through the exhaust ports 6 to the atmosphere, and a small `portion passes through the transfer port 9,

n scribed.

As the pist-on 8 passes downward, it opens the exhaust ports 6 fully, as well as the transfer port 9, permitting the burned-out gases free exit .through theexhaust ports, reducing the pressure in the working cylinder 1, and permitting the free passage of the hot fuel from the auxiliary cylinder 2 into the workingcylinderl, through the transfer port 9. j This flow `of hot fuel is deflected upward by the dcflector 32 on the upper end of the lip 10, as shown in Fig. 8. Since Athe port 9 is above the exhaust ports 6., and the deilector sends this stream of fresh `fuel upward, it is evident that there will be but very small quantity of ths fresh fuel which will escape through the exhaust ports; By the time that the crank-shaft 24 has reached the position shown in Fig. 4, the working piston 8 is substantially stationary but the auxiliary piston 19 is moving upward at a high speed and therefore is transferring the fresh fuel from the auxiliary cylinder, at a comparatively low pressure, into the working cylinder. Then, as the crank-shaft 24 turns further, the working piston 8 rises suiiiciently to close the exhaust ports 6, and the transfer port 9 is simultaneously closed by the lip 10. The rising auxiliary piston increases the pressure in the auxiliary cylinder 2 until, when the piston 8 vhas risen a short distance further, the said transfer `port 9 is again opened by the passage 33 through the lip 10 and this slightly compressed fuel is passed vtherethrough into the working cylinder.

The port 9 remains lopen until the auxiliary piston 19 has reached the upper end of its stroke and has transf-erred all of its fresh fuel int-o the working cylinder 1, for compression, as above described and as illustrated in F ig. 13.

Having, therefore, described my invention, what I claim is j 1. In an internal combustion engine, the combination of a working cylinder; a piston in said working cylinder; an exhaust port in said working cylinder, adapted to be uncovered by said piston as it approaches the lower end of its stroke; an auxiliary cylinder; a piston in said auxiliary cylinc er; mechanical means positively connecting the two said pistons together whereby the pressure in the auxiliary cylinder is substantially lower than that in the working cylinder at the lower part of the working stroke thereof; a transfer passage joining the working and auxiliary cylinders together, and adapted to be uncovered by said piston in the working cylinder substantially simultaneously with the uncovering of said exhaust port thereby; and a valve in said transfer passage adapted to open said passage to vpermit a portion of the exhaust in said working cylinder; an exhaust port in said working cylinder, adapted tol be uncovered by said piston as it approaches the lower end of its stroke; an auxiliary cylinder; a piston in said auxiliary cylinder and moving upward therein at the lower end of its stroke when said working pistonis uncovering the exhaust port ofsaid working cylinder whereby the pressure in the 'auxiliary cylinder is substantially lower than kthe simultaneous pressure in the working cylinder; a transfer passage joining the working and vauxiliary cylinders together, and adapted to be uncovered by said piston in the working cylinder substantially simultaneously with the uncovering of said exhaust port thereby; and a i valve in said transfer passage adapted to open said passage to permit a portion of the exhaust gases to pass into said auxiliary cylinder after .said passage and the exhaust port have been uncovered by said working piston.

3. In an internal combustion engine, the combination of a working cylinder; a piston in said working cylinder; an exhaust port in said working cylinder, adapted to be uncovered by said piston at the lower end of its stroke; an extension to the upper surface of said piston; a passage through said extension and forming a port within said working cylinder; an auxiliary cylinder; a transfer passage joining said working and auxiliary cylinders together, and adapted to be uncovered by either the upper edge of said piston extension or by said passage through said piston extension, as said working piston moves upward from the lower end of its stroke; a piston in said auxiliary cylinder moving upward to eject the gas therein into said working cylinder, through said connecting passage and above said piston extension when the working piston is at the lower end of its stroke, and through said passage throughsaid extension when the working pistonV is moving upward at about one-half its stroke.

4. In an internal combustion engine,'the combination ofa working cylinder; a piston in said working cylinder; an extension to the upper surface of said working piston; a passage through said extension and forming al port within said working cylinder; an auxil- `iary cylinder; a piston in said auxiliary cylinder; mechanical means positively connecting the said two pistons together, whereby the auxiliary piston is substantially in advance of the working piston; a transfer passage joining said working and auxiliary cylinders, said passage being adapted to be uncovered on the working cylinder end by the upper edge of said piston extension or by said passage therethrough as said working piston moves adjacent the lower end of its stroke; an exhaust port in said working cylinder adapted to be uncovered by said working piston as it approaches the lower end of its stroke; an inlet port in said auxiliary cylinder; means of valving said inlet port and the auxiliary cylinder end of said transfer passage, said valving means being operated by said mechanical means substantially in ad- Vance of said auxiliary piston, whereby said inlet valve is closed near the end of the downward motion of the auxiliary piston and the pressure in said auxiliary cylinder is substantially lowered whereupon said transfer passage is opened by the working piston extension and said valving means and said exhaust port is uncovered by said working piston to exhaust the gases from said working cylinder and to admit a flash of said exhaust gases into said auxiliary cylinder. O

SCAR H. ERICKSON. 

